Section insulator



March 17, 1925. I

1,530,467 G. w. BOWER SECTION INSULATOR Filed Nov. 23, 1923 E -I1lV12l or: George WT Bower;

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Patented Mar. 17, 1925.

UNITED STATES PATENT OFFICE.

G-EORGE W. BOWER, OF SGHENECTADY,,1\TE W YORK, ASSIGNOR T GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK. v

6 SECTION InsULA'roR.

Application filed November 23, 1923. Serial No. 676,666.

To all whom z'fimag concern: Be it known that I, GEORGE V. Bow-En, a'citizen of the United States, residing at Schenectady, in the county of Schenectady, 'State of New York, have invented certain new and useful Improvements in Section Insulators, of which the following is a specification.

The present invention relates to overhead current conductors for electricrailways and more especially to section insulators .whereby a system of overhead wires is provided with definite points of division electrically so that any section may be cut out from the current supply, and rendered dead and safe for repairmen to work upon, etc., while the remainder of the system continues in condition for normal operation.

Practically all trolley'systems in use at so the present time require the overhead trolley wire to be tightly stretched, under a tension of one thousand to three thousand pounds,

and to be yieldingly supported. in the vertical plane so that upon passage of the our- :3 rent collector, pressing'upwardly against the under side thereof with a force of twenty-five to thirty pounds, substantially all the irregularities and variations in. height of the wire Wlll be uniformly over.

1:1) come by its freedom of movement vertically and in this way avoid or greatly minimize VibratFon or vertical swing of the trolley head which ordinarily at high speeds tends to jump from one point of low elevation to the next and in so doing causes injurious arcing between itself and the wire.

Whenever a body, such as a sectioninsulator, is applied to an overhead conductor it, by reason of its relatively greater inertia,

acts as a dead weight thereon and seriously interferes with the uniform floating or wave motion llUl'H'HLlly produced. .in the yieldably supported conductor upon the passage of the trolley; On account of the severe han1- nier blows a trolley strikes such a body ap plied to an overhead conductor when traveling at speed, it. is common'practice to ln'ing an electric street car almost to a stop as its trolley passes a circuit breaker and it is also common practice to disconnect the car circuit until the section insulator is passed in order to avoid injurious arcing.

On electrified steam railways and'other systems where long heavy trains are operated at speeds of a mile per minute, the current collector is o-fthe slider or pantographic typeand possesses'i 'elatively great inertia and n consequence of whlch the hammer blows resulting from the presence of any dead weight on the wire are excessive. Moreover, the troubles and expense lncidenta'l' to-the slowingup of such a train to enable the trolley'to pass the section insulators quietly are'too great to be tolerated byrailway operators. The object of my invention is to provide an improved section insulator :which will operate satisfactorily under severest operating conditions, which will be hardy and durable, and which may be easily and quickly repaired by ordinary workmen. I '1 One, embodimentofthe invention is shown in the accompanying drawing, in

which Fig. 1 is a top plan view of my section insulator, and ,Fig. 2 is a side elevation thereoff a The main frame of the device is generally pH-shaped and consists of a longitudinal metal bar rl, preferably made tubular for the sake of 'lightness,--with a cross or spreader bar '2'urigidly connected, as by welding, to each end thereof. The outer ends-of the cross bars 2 are provided with lugs 3 whereby the device may be attached to suspension Wll'BS. On each arm of the cross bars 2 is-mounted a spool insulator 4: having a series of annular corrugations on opposite sides ofa cylindrical center portion 6'. Metal brackets 7, 8, 9, and 10 ,3

having circularly recessed heads are .attached to the cylindrical center portions 6 byclamping plates 11 and bolts 12 andare thus electrically. insulated from the frame.

The brackets 8 and 10, at the rearleft and front right-hand corners of the frame 'as-shown in Fig.1, are in the form of vertical posts with. three cross pins or points of-attachment 13, 14B and 15 atthe lower ends thereof. he other brackets 7 and 9 have three attachment cars 16, 17, and 18, arranged substantially radial to the axis of the respective cross bar 2.

The trolley wire 19 is of coursesevered for the introduction of the section insulator and each of the severed ends is clamped to a strain block or coupling adapted to be pinned to the respective post brackets 8 and 10 at the connecting points 15 and the tension of the trolley wire exerted thereon is taken up by tie rods 21 extending diagonally upward from attachment points .13, opposite the attachments 15, to the attachment cars 18 on the respective brackets 7 and9 and from these points the tension is taken up by anchor wires 22 interrupted by strain insulators 23 arranged in pairs. The opposite ends of the anchor wires 22 are attached to strain ears, 2 l secured to the trolley wire sections 19 a considerable disiance, about fifteen feet, from the respective ends-thereof so thatthe stresses exerted on the anchor wires 22 are on a linesubstantially parallel to the trolley wire. l n order to provide trackage for the trolley bevneath the insulator, a flexible conductor stripof hard drawncopper-is bolted toeach of the bracket arms ITand-bent downwardly on a long radius adjacentthereto,-andthen extended horizontally beneath the resp entire post bracket 10 by which it is; supported flexiblyby an, car 26 [havinga vertical slot .27 wherebyit may move freely up and down a limiteddistance onthe supporting pin 14, and ,beyond; the ear 2.6 it is bent upwardly through a small angle toprovide a gradual incline 28 to the trolley wire 19 to which it is attached by a guide ear .23)v intermediate the points of attachmentof the strain-block 2,0 and the strain ear 2 1 thereto. v v

If it be assumed thatrai current collector of the pantograph type approach thesection insulator from the right-hand, it wilt contact with the. guide bracket 2-9.,rwhich being supported by a. straight section of trolley wire isfree to.- move upwardly without per- -ceptible effect on the collector; Such lifting efteot as the-collector produces in pass ing beneath the guide; ear 29 and the inclined portionofthe-track strip-25 operate to rock the section linsulator about its longitudinal axis soras to depress :the opposite track strip. 25 into position to be engaged at its curved portion by the collector after the latter has traveled a considerable dis .tance alongthe other track strip During the time the collector is in contact with both strips it tendsutol restore thesection insuilator to its original position. Upon the departure of the collector from the .rear end of the first track strip the section insulator he "ins to rock on its axis in the opposite i'l-ireotion. and; slightly elevates the end of the lett-hand section of the trolley wire 19 so that it 1; s, thereto without perceptible impact. In fact, it has been. determined by actual use that each of the five points of changing contact is passed serially by the collector without perceptible shock or :disturbance to the overhead structure or to the collector.

-l-n casethe'flexible track strips or their attachments should become worn, they may be removed and replaced without disturbing any otherpart of the insulator or the tension of thetrolley' wire.

While I have shown and described the best" embodiment of the invention known to me, I do not desire to be restricted thereto. hat I; claimvas'new and desire to secure by Letters Patent of the United States, is

1. A section insulator comprising a frame, :two spaced conductor trackssupported at opposite sides. thereof and each provided with. a flexible inclined end having provision for attachment to the'respective trolley wire sections, and attachment means for the ends ofthe trolley Wire sections connected to said frame independent of said conductor tracks.

2'. A section insulator comprising a frame,

two spaced conductor tracks yieldably supported beneath the said frame and at oppov site sides thereof and each provided at one end with-a flexible inclined portion having provision for attachment to the respective trolley wire sections, and strain attachment means for'the ends of the trolley wire sections connected to said frame independent bracket-s, insulated strain means connected to said'ibrackets and to said frame for transmitting the tension. of one trolley wire section tov the opposed wire section, and two spacedconductor tracks of flexible material adapted to be connected to the respective trolley wire sections, to the respective brackets, and to the opposite ends of the .iirame;

4.1; section insulator comprising an H -shaped frame having two vertical post brackets at diagonally opposite corners thereof and attachment brackets at the remaining corners, tie rods connecting the lower end of each post bracket with the attachment bracket on the respective sides of said (frame, means for attachment of the ends of the trolley sectioi-is to said post brackets, :and two flexible conductor tracks freely suspended from the lower ends of said post brackets and having the ends thereof detachably connected to the respec tive attachment brackets and to the respective trolley wire sections.

In witness whereof, I have hereunto set my hand this. 22nd day of November, 1928,

- GEORGE W. BOlYER. 

